Add extra sanity check for btrfs_ioctl_defrag_range_args::flags.
This is not really to enhance fuzzing tests, but as a preparation for
future expansion on btrfs_ioctl_defrag_range_args.
In the future we're adding new members, allowing more fine tuning for
btrfs defrag.
Without the -ENONOTSUPP error, there would be no way to detect if the
kernel supports those new defrag features.
cc: stable@xxxxxxxxxxxxxxx #4.14+
Signed-off-by: Qu Wenruo <wqu@xxxxxxxx>
---
fs/btrfs/ioctl.c | 4 ++++
include/uapi/linux/btrfs.h | 2 ++
2 files changed, 6 insertions(+)
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index a1743904202b..3a846b983b28 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -2608,6 +2608,10 @@ static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
ret = -EFAULT;
goto out;
}
+ if (range.flags & ~BTRFS_DEFRAG_RANGE_FLAGS_SUPP) {
+ ret = -EOPNOTSUPP;
+ goto out;
+ }
/* compression requires us to start the IO */
if ((range.flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
range.flags |= BTRFS_DEFRAG_RANGE_START_IO;
diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h
index 7c29d82db9ee..48e9b7ffecf1 100644
--- a/include/uapi/linux/btrfs.h
+++ b/include/uapi/linux/btrfs.h
@@ -614,6 +614,8 @@ struct btrfs_ioctl_clone_range_args {
*/
#define BTRFS_DEFRAG_RANGE_COMPRESS 1
#define BTRFS_DEFRAG_RANGE_START_IO 2
+#define BTRFS_DEFRAG_RANGE_FLAGS_SUPP (BTRFS_DEFRAG_RANGE_COMPRESS |\
+ BTRFS_DEFRAG_RANGE_START_IO)
struct btrfs_ioctl_defrag_range_args {
/* start of the defrag operation */
__u64 start;
--
2.43.0
